There are many shades of blue and you don't specify which color of blue your carpet is. Anyway, blue goes with many colors. It is usual to paint the walls the same color as your carpet or a lighter shade, which will make your room appear larger. White and yellow will give the room a french country look as will adding red. Or you could go for blue and white and add touches of a stronger color such as yellow, or if your furniture is dark wood then the brown of the wood is a third color. It is important to find the style you like. I would go online and type "color scheme ideas for blue carpet" in the search field and click on the "images" and see what you like.